Change Passcode: Enter a new six-digit passcode. Or tap Passcode Options to switch to a four-digit numeric code, a custom numeric code, or a custom alphanumeric code.

Require Passcode: As soon as you lock your screen, the default for this setting will ask you to enter your passcode to unlock. If you don't want an immediate passcode requirement, change this setting. (For your own security, if you use Touch ID or Apple Pay, you can't change the immediate passcode requirement).